Author Topic: New to me 750K7! Few issues to address  (Read 6331 times)

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Offline SierraCB

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Re: New to me 750K7! Few issues to address
« Reply #50 on: April 14, 2015, 03:44:58 PM »
Just checked the timing.  It looks really close, as in the tick for F is as close as it can be without being dead on.  I'm totally out of adjustment though, is this normal?  I can't rotate the plate any farther.  The other cylinders are in the same spot.  Bike is running a tad better but just can't figure out why it doesn't like to just run a smooth idle. 

Offline Stev-o

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Re: New to me 750K7! Few issues to address
« Reply #51 on: April 14, 2015, 04:35:45 PM »
Just checked the timing.  It looks really close, as in the tick for F is as close as it can be without being dead on.  I'm totally out of adjustment though, is this normal?  I can't rotate the plate any farther.  The other cylinders are in the same spot.  Bike is running a tad better but just can't figure out why it doesn't like to just run a smooth idle. 

Running out of adjustment is typical when cheap Chinese points are used.   Are they new?
I suggest buying Honda points if you can.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline flybox1

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Re: New to me 750K7! Few issues to address
« Reply #52 on: April 14, 2015, 08:18:54 PM »
Just checked the timing.  It looks really close, as in the tick for F is as close as it can be without being dead on.  I'm totally out of adjustment though, is this normal?  I can't rotate the plate any farther.  The other cylinders are in the same spot.  Bike is running a tad better but just can't figure out why it doesn't like to just run a smooth idle.
Might need to verify your timing plate does NOT have any play writhing the confines of its support posts.  It is a common timing fix to take up any play with a metal shim, secure the three mount screws, and then set the timing.

What points are you running?  ND, TEC, Daiichi?
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline SierraCB

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Re: New to me 750K7! Few issues to address
« Reply #53 on: April 14, 2015, 10:29:47 PM »

Just checked the timing.  It looks really close, as in the tick for F is as close as it can be without being dead on.  I'm totally out of adjustment though, is this normal?  I can't rotate the plate any farther.  The other cylinders are in the same spot.  Bike is running a tad better but just can't figure out why it doesn't like to just run a smooth idle.
Might need to verify your timing plate does NOT have any play writhing the confines of its support posts.  It is a common timing fix to take up any play with a metal shim, secure the three mount screws, and then set the timing.

What points are you running?  ND, TEC, Daiichi?

I'll have to check. I think they are TEC...

I don't think it has any plate. It's not visually at least.

Offline Stev-o

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Re: New to me 750K7! Few issues to address
« Reply #54 on: April 14, 2015, 10:59:39 PM »

Just checked the timing.  It looks really close, as in the tick for F is as close as it can be without being dead on.  I'm totally out of adjustment though, is this normal?  I can't rotate the plate any farther.  The other cylinders are in the same spot.  Bike is running a tad better but just can't figure out why it doesn't like to just run a smooth idle.
Might need to verify your timing plate does NOT have any play writhing the confines of its support posts.  It is a common timing fix to take up any play with a metal shim, secure the three mount screws, and then set the timing.

What points are you running?  ND, TEC, Daiichi?

I'll have to check. I think they are TEC...

I don't think it has any plate. It's not visually at least.

The "plate" that Fly is referring to is the part your points are screwed to. 
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline SierraCB

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Re: New to me 750K7! Few issues to address
« Reply #55 on: April 14, 2015, 11:03:04 PM »


Just checked the timing.  It looks really close, as in the tick for F is as close as it can be without being dead on.  I'm totally out of adjustment though, is this normal?  I can't rotate the plate any farther.  The other cylinders are in the same spot.  Bike is running a tad better but just can't figure out why it doesn't like to just run a smooth idle.
Might need to verify your timing plate does NOT have any play writhing the confines of its support posts.  It is a common timing fix to take up any play with a metal shim, secure the three mount screws, and then set the timing.

What points are you running?  ND, TEC, Daiichi?

I'll have to check. I think they are TEC...

I don't think it has any plate. It's not visually at least.

The "plate" that Fly is referring to is the part your points are screwed to.
I meant to say play, sorry!

Offline SierraCB

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Re: New to me 750K7! Few issues to address
« Reply #56 on: April 16, 2015, 11:52:35 AM »
UPDATE. 

I was able to take the bike for a 10 miles ride today... The first 5 mins sucked as usual since it just HATES to idle when it's cold.  Maybe I am expecting something that i'll never get from the bike?  I set the warm idle around 1500-1600 and it likes it right there.  Any lower and it just doesn't feel happy.  Other than that, this bike runs killer!  Acceleration is linear and quick. Generally settling down to its happy higher than normal idle.  The noise in the motor is much better when warm and after the tune up I did.  There is still a bit of a weird sticky valve or something sound but it seems okay.  Time to tackle steering stem bearings... oh boy

Offline flybox1

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Re: New to me 750K7! Few issues to address
« Reply #57 on: April 16, 2015, 12:33:58 PM »
My K8(F3engine) prefers 2500rpm at start-up, and it'll hang there with full choke.. 
Once the engine warms, the rpms start rising, which is the bikes cue to me to take the choke off.
Not all at once, but in (probably) thirds.  When the last bit of choke is removed, it'll settle nicely around 1300rpm.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline Stev-o

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Re: New to me 750K7! Few issues to address
« Reply #58 on: April 16, 2015, 04:24:23 PM »
These tachs are not super accurate, I typical set the idle "by ear". Put soe miles on the bike, it could get better.

Have you read the Taper Bearing Thread? Go grab a couple beers....

http://forums.sohc4.net/index.php/topic,1516.0.html
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline Mr. Mike

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Re: New to me 750K7! Few issues to address
« Reply #59 on: April 17, 2015, 09:47:09 PM »
This idle business with the K8 is interesting to me too. I've had a Honda 750 20 year mechanic tell me when starting cold, to do similar as to what Flybox said. I had to get used to being geared up and ready to go, no standing by waiting for the cold engine to warm up, but crack the throttle one time (some will disagree here), pull the choke fully and hit the start. Idle wails up to around 3k and then begins to move down. once it starts to move down, push the choke about 1/3 in and get on the thing and go. A few minutes down the road, push it in a bit more and in less than 10 minutes of riding it'll idle around 1k with the choke fully in. Eventually when really warmed up, the idle will settle around 11 hundred, but the clutch rattle is still present. Clutch in at idle, not so bad.
2002 Electra Glide
1978 750K
1966 CL77 (sold)
2020 CB500X